Research On Whole-Span Double-Line Box Beam Pre-cast Technology Of Transportation Of Special Railway Line

The passage studies and concludes whole-span double-line box beam pre-cast technology of transportation of special railway line, on the basis of mass research of completed projects at home and abroad, as well as scrutiny of domestic programs under construction, aiming at presenting necessary technological support and theoretic guidance for the said technology to ensure that the quality of pre-cast box beam will meet the requirements of transportation of special railway line.It is started with the whole disposal of beam site. firstly, it is concluded of locating beam site and disposal, whole plan of beam site, and designs of beam pre-casting and beam bed, making efforts to let proposals be technologically liable while economically reasonable. It consists of complete process from model designing and mortar grouting by tensioning for beam pre-casting. According to examples, it is demonstrated several scientifically effective, economical and reasonable executing plans and arts.Besides conventional constructing methods and arts, with the purpose of the beam body for one hundred year use, another main point of the passage is the study of endurance of beam body. It is illustrated control on raw materials and coordinating ratio design, at the same time, it is comprehensively analyzed and researched into the use of strengthened concrete, protective course thickness of the beam body, locations of pre-stressed pipes, concrete curing, and controlling on concrete crack of beam body, as well as on concrete strength and flexible models, which lay great importance on guaranteeing the endurance of pre-cast beams.In the end, it is come up with some attentions and something still to be improved for further study in the future. As a result, a more technological, economical, reasonable and safer executing proposal will be achieved.